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=====Sublimation Refining of Arsenic=====
Although thermal separation separates gallium and arsenic fairly effectively, the arsenic can still be contaminated with more volatile contaminants like carbon. To further purify, the arsenic is put through through the process of sublimation refining. During sublimation refining, the arsenic is heated slightly above 610 degrees C, the sublimation temperature of arsenic. This heating is performed in an inert gas stream such as nitrogen, and the arsenic is transferred to and recondensed in a second chamber. To obtain higher purity arsenic, this process can be accomplished multiple times. This method works because arsenic and the impurities within will differ in partial pressures and volatility.[[File:Purification of Arsenic.jpg|thumb|left|Purification of As]]
=====Gallium Zone Refining=====<gallery>Image:Purification Gallium zone refining is a purification technique for gallium based upon low expectations of impurities. The process only works due to the near pure gallium obtained from thermal separation. To further purify, gallium is placed in a gallium refining pan with a spiral groove in the pan bottom, and cooled to 0 degrees C. A heat lamp is used to heat specific zones of Galliumthe gallium sample, and the pan is slowly rotated.jpg|Purification Based upon the temperature difference of solid and liquid in the sample, impurity segregation will occur, and impurities will segregate to both ends of GaImagethe spiral groove in the gallium refining pan.[[File:Purification of ArsenicGallium.jpg|thumb|right|Purification of As</gallery>Ga]]
====Downcycling====

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